On this website we have a tool that allows our visitors to browse the sounds that are referenced in the paper. Each sound is presented as a spectrogram of the sound and associated data of the recording. A spectrogram is a visualization of the energy in the sound file drawn in a plot of frequency (pitch) over time. This means that the from bottom to top, the frequency ranges from about 200 Hz to about 12 kHz. Most biological sounds are limited under 10 kHz, with some exceptions.
Frequencies with high energy have a bright color, while frequencies with little energy will appear dark. In this example, the yellow box has a lot of energy (therefore, loud sounds) and the red box indicates some frequencies with little energy (no, or faint, sounds):
Each sound file is available to listen as an MP3 file. There is a Flash-based MP3 player on the bottom of each spectrogram. This tool requires a modern browser (Internet Explorer, Firefox, Chrome, or Safari) with Adobe Flash installed as a plugin.
To listen to the sound, click on the playback button on the player:
The player will show a progress bar in yellow indicating how much of the file has been loaded. A green progress bar will indicate the current position. To stop playback, click on the pause button:
To jump playback to a particular position, click on the progress bar.
Click on the "W" to change the display to the waveform. Click on the "S" to switch back to the spectrogram.